Wash potatoes thoroughly and cook in boiling salted water for about 20 minutes. Drain, rinse with cold water and remove the skin. Let the potatoes cool down. Cut off fins and tail from the herrings.
Wash the fish, dab dry and sprinkle with lemon juice. Cut potatoes into thin slices. Peel and finely dice onions. Dice bacon as well and leave it crispy. Fry the onions briefly.
Boil up with broth. Remove from heat and season to taste with vinegar, salt and pepper. Add oil and pour everything over the potatoes. Mix loosely and let it stand covered for at least 30 minutes.
Dab herrings dry, season with salt and pepper and turn in flour. Tap off excess flour. Heat the remaining oil in a frying pan and fry the herrings for 5-6 minutes on each side. Wash the parsley and chop finely, except for a little to garnish.
Season potato salad again and sprinkle with parsley. Arrange fried herrings with parsley and lemon slices. Serve with the lukewarm potato salad.